The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 10, 1998
Filed:
Nov. 14, 1995
Takao Takehara, Iwata-gun, JP;
Minebea Co., Ltd., Nagano, JP;
Abstract
An inverter apparatus of the present invention has a cold cathode tube and its operating circuit provided with a piezoelectric transformer. Specifically, for increasing the boost ratio of the piezoelectric transformer, a boost chopper is mounted in the premier stage of a semi-class E voltage resonance inverter and a power switch element is mounted operable commonly for both the inverter and the chopper so that a single voltage resonance controller IC controls the cold cathode tube at a constant current. As the operating circuit is composed of the voltage transformer, the apparatus will be minimized in the number of components and decreased in the overall size and the production cost. Also, as the operating frequency of the cold cathode tube is increased by increasing the resonance frequency of the piezoelectric frequency, the discharge efficiency will also be enhanced.